Among the forest species adapted to the rigors of our climates, cedar, commonly called white cedar or eastern cedar, is the least expensive of all. It has good resistance to decay. However, it is a wood that tends to crack and sometimes some nodes end up yielding. Regular maintenance minimizes these characteristics.
Western cedar or red cedar is more expensive, but its durability is much greater; it is not subject to cracking and it retains well its nodes. This essence resists decay for decades even if it is not maintained.
Another highly efficient indigenous species in terms of resistance to decay, relatively expensive white oak is difficult to find in stores. It is very hard and very stiff wood.
Finally, two exotic species are available at selected specialty wood dealers. These are mahogany and teak. Many used in the construction of yachts and garden furnishings, these essences are in the case of expensive mahogany and in the case of teak very expensive.
In both cases, a regular maintenance will retain its original appearance although, in the long run, a coat of paint will cover them. Maintenance free, they will withstand the rot without a problem but will end up looking bad.
And if in some stores you are offered teak garden furniture at a good price, make sure they are actually in teak. Certain woods from Asia look like the teak without being.
From now on, microwave-treated woods and other techniques will replace the treated wood considered by many people who are harmful to the environment and to public health.
They are at first very stable since their water content is almost at 0. The insects are not interested. Finally, the roasting makes them brown more or less dark without hiding the grain of the wood. The most common species are pine, spruce, and American poplar, although all three types can be cut if you have a saw that is good enough. I’d recommend the SawStop PCS31230 for this purpose.
The available stocks of these new products are likely to be limited for a few years, making them an expensive product without being astronomical. In my opinion, red cedar represents the best value for money at the moment and for some time to come. However, if you want a distinctive and high-quality product for outdoor projects, you might want to take a look at it.
Finally, whatever your choice, the finishes that offer the best protection contain linseed oil. They have the advantages of being inexpensive, very easy to apply and they retain moisture from the wood. These finishes must be refreshed every two years, if not every year.
Urethane finishes seal surfaces and protect wood for long periods of time. However, they tend to crack and get damaged under the effect of the elements of nature. And when refinishing these surfaces, you have to scratch the old finish and sand it.
Finally, if you intend to paint or varnish your garden furniture or any piece of wood used outside, white pine can be an economical and appropriate solution provided the boards do not touch soil, nor be severely exposed to the elements of nature.